Acute phase protein response to viral infection and vaccination

Abstract

Organisms respond in multiple ways to microbial infections. Pathogen invasion tipically triggers an inflammatory response where acute phase proteins (APP) have a key role. Pentraxins (PTX) are a family of highly conserved APP that play a part in the host defense against infection. The larger proteins of the family are simply named pentraxins, while c-reactive proteins (CRP) and serum amyloid proteins (SAA, SAP) are known as short pentraxins. Although high APP levels have been broadly associated with bacterial infections, there is a growing body of evidence revealing increased PTX, CRP and SAP expression upon viral infection. Furthermore, CRP, PTX and SAP have shown their potential as diagnostic markers and predictors of disease outcome. Likewise, the measurement of APP levels can be valuable to determine the efficacy of antiviral therapies and vaccines. From the practical point of view, the ability of APP to reduce viral infectivity has been observed in several virus-host models. This has prompted investigation efforts to assess the role of acute phase response proteins as immunoregulatory molecules and their potential as therapeutic reagents. This work aims to present an overview of the APP response to viral infections reviewing the current knowledge in the field.

Distribution of serum amyloid A and establishment of reference intervals in healthy adults

“…Serum amyloid A is an important acute-phase reactive protein mainly produced by liver, which can eliminate pathogens in the body and facilitate disease recovery. 18,19 And thus, it is a very sensitive marker reflecting an acute inflammatory state. 20 This study combined the regional characteristics of population distribution and eating habits in coastal cities, established strict normative inclusion and exclusion criteria for reference individuals, and finally confirmed 2365 healthy people with physical examinations as the research cohort.…”

Associations between serum amyloid A, interleukin‐6, and COVID‐19: A cross‐sectional study

“…Therefore, it is important to identify the risk factors of COVID‐19 as early as possible so as to take appropriate interventions. Previous studies indicated that serum amyloid A (SAA) and interleukin‐6 (IL‐6) play important roles in viral diseases and were widely used in clinical laboratories as indicators of inflammation 13‐17 . So far, the cytokine profile including IL‐2, IL‐6, IL‐7, granulocyte colony‐stimulating factor, interferon‐γ, inducible protein 10, monocyte chemoattractant protein 1, macrophage inflammatory protein 1‐α, and tumor necrosis factor‐α has been considered to be associated with the severity of COVID‐19 18 .…”

Hypoalbuminemia in Severe COVID-19 Post Recovery Patients

“…However, our data is the rst study related to the COVID-19 post recovery patients. CRP is produced by the liver as a nonspeci c immune protein and it is considered as a signal of systemic in ammation 33 CRP level in serum also can be affected with the level of other serum proteins which are produced by liver cells 34,35 .…”